vsnprintf (9) - Linux Manuals
vsnprintf: Format a string and place it in a buffer
vsnprintf - Format a string and place it in a buffer
*buf, size_t size, const char *fmt, va_list args);
- The buffer to place the result into
- The size of the buffer, including the trailing null space
- The format string to use
- Arguments for the format string
This function generally follows C99 vsnprintf, but has some extensions and a few limitations:
n is unsupported p* is handled by pointer
See pointer or Documentation/printk-formats.txt for more extensive description.
** Please update the documentation in both places when making changes **
The return value is the number of characters which would be generated for the given input, excluding the trailing '\0', as per ISO C99. If you want to have the exact number of characters written into buf as return value (not including the trailing '\0'), use vscnprintf. If the return is greater than or equal to size, the resulting string is truncated.